/**
 * ***************************************************************************** Copyright (c) 2000,
 * 2006 IBM Corporation and others. All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0 which accompanies this
 * distribution, and is available at http://www.eclipse.org/legal/epl-v10.html
 *
 * <p>Contributors: IBM Corporation - initial API and implementation
 * *****************************************************************************
 */
package org.eclipse.jface.viewers;

/**
 * A content provider mediates between the viewer's model and the viewer itself.
 *
 * @see org.eclipse.jface.viewers.ContentViewer#setContentProvider(IContentProvider)
 */
public interface IContentProvider {
  /**
   * Disposes of this content provider. This is called by the viewer when it is disposed.
   *
   * <p>The viewer should not be updated during this call, as it is in the process of being
   * disposed.
   */
  public void dispose();

  /**
   * Notifies this content provider that the given viewer's input has been switched to a different
   * element.
   *
   * <p>A typical use for this method is registering the content provider as a listener to changes
   * on the new input (using model-specific means), and deregistering the viewer from the old input.
   * In response to these change notifications, the content provider should update the viewer (see
   * the add, remove, update and refresh methods on the viewers).
   *
   * <p>The viewer should not be updated during this call, as it might be in the process of being
   * disposed.
   *
   * @param viewer the viewer
   * @param oldInput the old input element, or <code>null</code> if the viewer did not previously
   *     have an input
   * @param newInput the new input element, or <code>null</code> if the viewer does not have an
   *     input
   */
  public void inputChanged(/*Viewer viewer, */ Object oldInput, Object newInput);
}
